Doors for high security prison cells and also for some rooms housing dangerous psychiatric patients in hospitals or psychiatric facilities are typically provided with an access opening to allow the passage of food, medication or other materials through the door without requiring the door itself to be opened. This access opening is also used for handcuffing inmates before the door to the prison cell is opened by having the inmate reach through the access opening for the placement of handcuffs before unlocking the door and removing the inmate therefrom. Typically, the access opening is small in relation to the door and is covered by a hinged panel that is locked in a closed position to permit the hinged panel to be opened when access is desired. In such situations, whether in a prison setting or a psychiatric facility, once the hinged panel is opened, the person on the other side of the door now has direct access to the person on the other side of the locked door. Accordingly, the inmate or psychiatric patient may throw hazardous materials, such as human waste, through the opened access opening, or try to grab and injure the guard or hospital worker. Accordingly, prison guards and hospital workers are exposed to possible danger from the confined inmate or patient when direct access is available.
A number of attempts have been made to limit the direct exposure between the inmate of psychiatric patient and the guard or hospital worker, and thus protect the guards and hospital workers by providing an access opening closure device on the outside of the locked door over the access opening. One such device is found in U.S. Pat. No. 6,302,325, granted on Oct. 21, 2001; U.S. Pat. No. 6,598,546, granted on Jul. 29, 2003; U.S. Pat. No. 6,817,481, granted on Nov. 16, 2004; and U.S. Pat. No. 9,016,558, granted on Apr. 28, 2015, all of which were granted to Thomson Alexander. These Alexander devices all have a frame that is affixed to the outside of the door over the access opening for which the sliding panel is preferably removed, which supports a trapezoidal box having a pivoted top lid that allows access to the interior of the trapezoidal box. Once an article, such as food, is placed into the trapezoidal box, the slide panel for the device can be opened to allow the person on the inside of the cell or room to access the article and take position thereof.
If the top lid of the trapezoidal box is closed before the slide panel is opened, the inmate or psychiatric patient does not have direct access to the guard or hospital worker. The problem with the Alexander device is that the top lid and the slide panel have lock mechanisms associated with them to prevent movement unless the lock mechanisms are unlocked, but once unlocked an open top lid would expose the prison guard or hospital worker to danger from the inmate or patient on the opposing side of the wall. Operating the lock mechanisms can be cumbersome particularly when the guard or hospital worker is carrying a tray of food or other large article. In some cases, guards and hospital workers take shortcuts without reengaging the locks on the top lid and/or slide panel to facilitate the next operation to bring articles to the inmate or patient. Furthermore, with the hinge for the top lid being at the front of the pass through box, the top lid requires a significant amount of pivotal movement from the closed position thereof to the fully opened position to enable the placement of a tray of food into the trapezoidal box, and all of this weight on the hinge subjects the hinge to being damaged, resulting in higher maintenance costs.
A similar access opening closure device is disclosed in U.S. Pat. No. 6,378,769, granted on Apr. 30, 2002, to Steven Wolgamot, in which the box is rectangular and provided with a front hinged door. The box includes an overcenter clamping apparatus that allows the rectangular box to be portable from one door to another. In operation, the guard secures the rectangular box to the channel of the slide panel for the access opening by securing the latch mechanism to the channel and securing the overcenter latch. The front door can then be opened to insert a tray of food, as an example, into the rectangular box, after which the front door can be locked into a closed position. Then the slide panel is moved to allow the inmate on the opposing side of the door to remove the tray or other article. After the slide panel is locked in the closed position, the rectangular box can be unlatched from the channel of the slide panel to allow the rectangular box to be removed.
U.S. Pat. No. 6,588,655, granted to James Stapleton, Jr., on Jul. 8, 2003, discloses a non-contact food pass and access device similar to that described above with respect to U.S. Pat. No. 6,378,769. The Stapleton device also includes a rectangular box having a hinged front door and an overcenter clamping mechanism that engages the frame channel corresponding to the slide panel for the access opening through the door. In the Stapleton device, the rectangular box is shown as being co-operable with a guillotine style of slide panel in which the slide panel moves vertically rather than horizontally. The operation is substantially the same. The rectangular box is detachably connected to the frame channel of the slide panel through an overcenter clamping mechanism. The front door is opened to allow the insertion of a food tray, as an example, before the front door is closed and latched and then the slide panel moved to permit access to the interior of the rectangular box by the inmate.
All of these conventional access devices utilize a lock mechanism to control the movement of the slide panel and preferably also the door through which access to the interior of the box by the guard or hospital worker can be had. The more locks that are used, the more cumbersome the operation of the closure device becomes.
It would, therefore, be desirable to provide an access opening closure device that is simple to operate without compromising the safety and security of the person operating the closure device, and to provide a closure device that can be opened and closed in an instant, and a closure device that protects the prison guard or hospital worker when the pass through box is opened.